Investigation of ascorbate peroxidase, catalase, and superoxide dismutase gene expressions at the MRNA level after the applying of various boron salts in wild olive (olea europaea var. sylvestris) plant growed in vitro

Various biotic and abiotic stresses affect plant growth, development and crop productivity. Plants have developed many complex strategies such as adapting, defending, avoiding and tolerating all these stress conditions. Adaptation strategies can be at the morphological, physiological, molecular, biochemical, or epigenetic levels. Changes such as ROS signal, accumulation of plant growth regulators such as salicilic acid, jasmonic acid, absisic acid, ethylene, and inorganic ion flux are some of the basic mechanisms that affect the plant's adaptation to environmental stress conditions. In this thesis study, it was aimed to examine the relative mRNA levels of antioxidant enzymes under oxidative stress conditions of the olive plant, which is difficult to micro-propagate in vitro, and to find suitable development conditions. In this context, three different compounds of element B, which are known to be effective in oxidative stress conditions by acting on the ascorbate glutaion pathway, were added to the nutrient medium of the olive plant, which was transferred in accordance with in vitro conditions, in two different doses. As a result of the study, it was observed that the relative mRNA expression levels of antioxidant enzymes decreased in only one of the experimental groups. An increase in the relative mRNA expression levels of antioxidant enzymes was observed in other experimental groups compared to the control group. This situation was interpreted that the other compounds applied increased the salinity stress of the plant due to being salt and accordingly the oxidative stress increased. However, the decrease in the relative mRNA expression level of antioxidant enzymes in only one dose of a compound reveals that the dose is also effective with the compound. Since the study was carried out only on the relative mRNA expression levels, it should be noted that the data obtained can be interpreted only on the mRNA levels, and the data may change at the protein level. Keywords: APX, CAT, mRNA, Olea europaea, SOD, qRT-PCR